Explosive powder



'ers skilled in the art to which UNI ED S E PATENT OFF CE.

. WILLIAM R. QUINAN, or'snu FRANCISCO, CALIFORNIA.

EXPLOSIVE OWDER.

srncmrcnzrroiv' forming part or Letters Patent no. a'oopsaoma July 11,- 1882.

Application filed October 14,1881. (Specimens) i I To a-ll'whom it may concern: 7

Be it known that I, WILLIAM R. QUINAN, a citizen of the United States, residing at the city of San Francisco, county of San Francisco, and State of California, have invented certain new and useful Improvements in Explosive Powders, of which the following is a full, clear, and 'exact description, which will enable othit appertains to makeand'use the same.

My invention relates to that class of detonating-explosives which more or less resemble:

- gunpowder in their strength and mode of action, and are known as low powders, in contradistinctionto the stronger grades of detonating explosives. t

The object of my invention is to make alow powder which can'be readily exploded by the ordinary blastiu' -cap by using a small proportion of nitro-g ycerine iu'combination with other-ingredients whichform the ,essential elements of gunpowder.

It isa well established principle that avery smalltpercentage of nitroglycerine will detonate orcause 'the sudden conversion into gas of gunpowder and analogous mixtureswhen the 'nitro-glycerine itself is detonated by the 'fulminate cap. The dificnlty to be overcome in making a low powder on this principle is to retain such small percentage of nitro-glycerine in snch'a state that though distributed in the mixture it can be readily detonated.

' When asmall proportion of nitro-glycerine is mixed with the pulverized ingredients of guupowder or analogous.gas-producing mixtures it is so taken up and held that the ordinary blasting-cap will not detonate it.

The substances ordinarily usedin forming with nitro-glycerine the stronger or high explosive powders may be classed as porous sub-.'

stances or absorbents proper and non-porous substances, or those which hold the uitro-glycerine by surface attraction. The power otlthis surface attraction for nitro-glycerine-varles with difl'erent non-porous or non-absorbent substances. Some possess it slightly, and certain-oily substances exercise afeeble repulsion;

f Whatever power of surface attractioua nonporous substance may possess HHS plain that the amount of nitro-glycerine which will be taken up and held by a given weightpf anv such substance depends on the ex tent of surnew surfaces are formed, giving with every division an increasing surface of attraction.

the particles of nitro-,

Owing to this attraction glycerine are separated-more and more by being made to cover more surface, until if the process of division be carried far enough the nitro-glycerine ceases to give any indication of its presence as a liquid and loses the property of detonation by the ordinary cap. The greater the specific attraction of the substance for nitro-glycerine the more rapidly and readily will the extension of the surface bring about this condition of attenuation. The nitrates of soda and potash and the various-other'explosive salts used as oxydizing agents in nitro-glycerine powders belongto this class of non-porous or non-absorbent substances which hold the nitro-glycerine by surface-attraction. Their specific attraction for nitro-glycerine is com;

paratively strong. Heretofore in forminghigh explosive powders with nitro-glycerine these nitrates or other explosive salts have been pul verized or.rednccdto fine particles. Owing to their great extent of surface in a given weight, these particles will take up and render practicallyiuexplosive the small proportions of nitro-glycerinedesirable to use in low powders. This result, being in all essential respects the same as that given by the employment of veritable absorbents or porous substances, h as probably caused the value in the problem of making low powders of the distinction between the action of veritable porous absorbents and such non-porous or surface-attracting sub;

stances to be hitherto overlooked. Thus another inventor has found a means of counteracting this so-called absorption" of the nitroglycerine by coating or varnishing the pulverized salts usedwith some substance having less attraction than such salts for the nitroglycerine. I am the first to discoverthe cause of the failure to produce a low powder from the mixture of such explosive salts and small proportions of nitro-glycerine-viz., the great extent of surface attraction exercised by too salts in. the pulverized condition in which they have been hitherto employed-and the remedy for this so-called absorption without changa! in g thecharacter of. thqsurfacd-via, to lessenits extent by employing'the salts in the form of larger masses or grains.

The carbonaceous ingredient or ingredients or the element which in the explosion furnishes the carbon or hydrogen or both to unitewith the oxygen of the nitrate or other explosive salt may be one or several of a great variety of substances. 1 For the purposes-of my inven its condition is suehgas-tq leave the nitro-glyc erine free when the t'mo'are mixed, it is easy to, find acarbonac'eous'element sufiiciently nonabsorbent to be added in properly small proportion to the mixture without destroying the susceptibility of the nitro-glycerine to deton-' ation by the cap. Almost any hard or dense form of carbon or hydrocarbonwill fulfill this condition. 7 1 1 Sulphur is an element which is non-porous or non-absorbent, and has a comparatively 'feeble attraction for nitro-glycerine, As a regularly-granulated form of sulphur is not easily obtainable, I prefer to use a form of carbon which,'with the nitrate or other explosive salt, will leave the nitro-glycerin'e so free that the sulphur may be added pulverized.

The following is a typical example of. my invention: Unground nitrate of soda or cubic niter is taken in the crystallized commercial form and run through a sieve having twelve meshes to the linear inch. 0f the crystals or grains which pass through this sieve I mix sixty-seven parts, by weight, with fifteen and a half parts'rape-seed, twelve and a half parts pulverized sulphur, and five parts nitro-glycer-- ine. If the nitrate of soda has absorbed moistnre, it should be dried before using. The or-- der in which the ingredients are mixed is immaterial, though it is more convenient to add the nitro-glycerine last. After all the materials are in, thorough mixing can be obtained by running them through a coarse sieve.

For the nitrate of soda any other explosive salt that can be used as an oxidizing agent such as the nitrate of potash, of baryta, of lead, Ste-may be substituted. The nitrate of soda is to be preferred on account of its cheapness and the greater regularity of its granulation. in the crystal form. If any part of it should 'be pulverized by accidental attri- .by other means.

amounts of oxygen, as in resin, will not seriously impede the explosive reaction.

The proportions of nitrate or other explosive salt and the carbonaceous element should be adjusted by the chemical composition of the latter. Thereshould be enoughmxygen furnished by the nitrate or explosive salt to oxidthe powders it should be borne in mind that the nitro-glyeerine should-be so well distributed and securely held that there is no danger of leakage, and at the same time it should rema' gjfree enough to be readily detontdthat; the powders should not be wet,I-neither should they be too dry. The meshes of the sieve through which the nitrate of soda or explosiv'e salt is passed may vary in size from that given above as greater or less proportions of-nitro-glycerine are designed to be em ployed. The finer the grains of nitrate of soda or explosive salt the more nitro-glycerine they will take up. For larger proportions of nitroglycerine the finer sieves may therefore be used for the nitrate; or the carbonaceous ingredient may be wholly or partly pulverized.

For smaller proportions of nitro-glycerine coarser sieves may be used for the nitrate or explosive salt; or the sulphur may be reduced in quantity, or the whole or part of it may be used in the granular form. The proper combiuations of these alternatives will enable the powder-maker to prod uce-a variety of. low powders, each having its special application in blasting, and all of which are safe against leak ageot' the nitro-glycerine action of the cap.

In making this powder the unground crystallized nitrate may be used eflicicntly without passing it through the sieve. Regularity of granulation, though desirable, is not essential.

For the purposes of this invention the granulation of the nitrate or other explosive salt used, and of the sulphur, and even of certain forms of carbon, may be effected by fusing each separately and running it through a sieve, or For convenience the crystallized form of the nitrate is to be preferred. If the sulphur is to be grained, it can be done and susceptible to the by breaking up roll-sulphur.

The essence of my invention consists in utilizing the principle of surface attraction. WVithout changing the character of the surface of masses or pulverized grains in the mixture, and a small proportion 15 7 scones v portions to moisture. Itsother advantages are its se'nsitiveness to the cap, cheapness, and p the small amountof labor required in making it.

I claim anddesire'to secure 1.' A low explosive composition consisting of an untriturated' nitrate-such asnitrate of soda-in the form of .small crystals of determinate size, sulphur, pulverized or grained, carbonaceous material, either pulverized or in the form of non-porous small grains of determinate size, the uningredients remaining as separate of nitro-glycerine, which forms a coating in immediate contact with said small masses or grains, whereby the surfaces of the ingredients are so limited in extent as to retain the small by Letters Pat- I ent of the United States as myinventionmasses, grains, or,

proportion of nitro-glyeerine susceptible to detonation by the ordinary blasting-cap, substau:

tially as described.

2. The process of making a low explosive composition, which-consists in mixing crystals of nitrate of soda or its equivalent and carbonaccous material, as specified, either pulverized or in small non-porous masses oreoarse grains of definite regulated size, the unpulverized ingredients remaining as separate grains in the mixture, mixing therewith sulphur inpowder or grains, and adding asmall proportion of mtro-glycerine, substantially as described.

Dated at San Francisco October 6, 1881.

WILLIAM RUSSELL "QUINANr Witnesses:

J 01m A. WRIGHT,

Grms. D. WHEAT. 

